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Near 4,000 of plastic balls, made from Polyoxymethylene (POM) with diameter of approximately 2 mm (precisely 1.992 ± 0.015 mm), were poured into a cylinder of inner diameter 26.1 mm and of height 48.9 mm. Then, vertical vibrations of the cylinder attached to the vibration table Vibrax (Renfert GmbH, Germany) were applied to change the initial random loose packing (RLP) structure/ordering into denser and more ordered ball configurations. Tomographic measurements and analysis of its data (details given in the paper1) enabled to determine centres of all the balls closed in the cylinder. Their x, y, and z coordinates have been saved in three files BallBed_*-xyz.dat representing characteristic ball ordering. The image rendering software POV-Ray was used to visualise the external view of ball beds of: (i) the RLP structure (video 1), (ii) horizontal row (HR) structure (video 2), and (iii) vertical row (VR) structure (video 3). The HR configuration is commonly formed, while the VR one is very rare. Since both of them revealed existence of hexagonally-packed layers, each located around the cylinder axis, views of all these layers are presented in videos 4 and 5, respectively. The Coordination Polyhedron Method2, applied to an analysis of internal structure (i.e. arrangement of balls in the bed), revealed four types of regular structural units, each composed of 13 balls: (a) face centred cubic (represented in the videos by the unit central ball of blue colour), (b) hexagonal close packed (yellow), (c) icosahedral (red), and (d) decahedral (green). The attached videos 6, 7 and 8, show location of the central balls of all regular local structures.
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